## Here is an example for Autoconf.
syntax autoconf "\.(ac|m4)$"
comment "#"
# Keywords:
color yellow "\<(if|test|then|elif|else|fi|for|in|do|done)\>"
color yellow "(=|!=|&&|\|\|)"
# Macros:
color cyan "\<[[:upper:]_[:digit:]]+\>"
# Version numbers:
color red "\<[-_.0-9]+\>"
# Strings:
color red "\"[^"]*\"" "\'[^']*\'"
# Backticks:
color green "`[^`]*`"
# Error lines:
color brightred "^\*\*\*.*"
# Brackets:
color magenta "\[|\]|\(|\)"
# Comments:
color blue "^[[:blank:]]*#.*" "\<dnl.*"
# Trailing whitespace:
color ,green "[[:space:]]+$"